A recent trend in court is for defense attorneys to introduce brain scans and other forms of biomedical information (BI) into criminal trials as mitigating evidence. The present study investigates how BI, when considered in combination with a defendant's childhood information (CI), can influence the length of a defendant's sentence. We hypothesized that certain combinations of BI and CI result in shorter sentences because they suggest that the defendant poses less of a threat to society. Participants were asked to read accounts of the trial of a murder suspect and, based on the information therein, recommend a sentence as if they were the judge. The defendant was diagnosed with psychopathy, but biomedical information regarding that diagnosis was included or excluded depending on the BI condition. The defendant was further described as growing up in either a loving or abusive family. The results showed that, if BI was present in the trial account, the defendant from an abusive family was perceived as less of a threat to society and received a shorter recommended sentence than if the defendant had been from a loving family. If BI was absent from the account, the pattern was reversed: the defendant from a loving family was perceived as less of a threat to society and received a shorter recommended sentence than if he had been from an abusive family. Implications for the use of BI and CI in court trials are discussed, as well as their relationship to free will and the function of punishment as retribution and utility. Copyright © 2015 John Wiley & Sons, Ltd.